The present invention relates to the application of miniature robot technology in cell operation and separation, and is especially one new kind of thermally driven miniature executor based on Parylene C polymer material and capable of realizing cell operation in liquid environment. The miniature executor has multiple cantilever beam structure fixed on silicon substrate, and each of the cantilever beams is a three layer structure with Parylene C sandwiched resistive material. The miniature executor is prepared through one MEMS planar printing process. The present invention has electrothermal braking effect, and Parylene C as one kind of thermally, electrically and chemically isolating material may keep the heater of resistive material from exposing in liquid, resulting in excellent biocompatibility and environmental suitability. The present invention realizes cell operation and separation under controlled temperature and may be used in automatic cell location, detection, injection and measurement.